Hydrocarbon conversion using molecular sieve ssz-75

ABSTRACT

The present invention relates to new crystalline molecular sieve SSZ-75 prepared using a tetramethylene-1,4-bis-(N-methylpyrrolidinium) dication as a structure-directing agent, and its use in catalysts for hydrocarbon conversion reactions.

This application is a divisional of U.S. Ser. No. 11/756,767 filed Jun.1, 2007, allowed, which claims benefit under 35 USC 119 of ProvisionalApplication 60/804,248, filed Jun. 8, 2006.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to new crystalline molecular sieve SSZ-75and its use in catalysts for hydrocarbon conversion reactions.

2. State of the Art

Because of their unique sieving characteristics, as well as theircatalytic properties, crystalline molecular sieves and zeolites areespecially useful in applications such as hydrocarbon conversion, gasdrying and separation. Although many different crystalline molecularsieves have been disclosed, there is a continuing need for new molecularsieves with desirable properties for gas separation and drying,hydrocarbon and chemical conversions, and other applications. Newmolecular sieves may contain novel internal pore architectures,providing enhanced selectivities in these processes.

SUMMARY OF THE INVENTION

The present invention is directed to a family of crystalline molecularsieves with unique properties, referred to herein as “molecular sieveSSZ-75” or simply “SSZ-75”. SSZ-75 is believed to have the frameworktopology designated “STI” by the IZA. Materials having the STI topologyinclude naturally occurring stilbite and the zeolite designated TNU-10.Stilbite is disclosed in Breck, Zeolite Molecular Sieves, 1984, RobertE. Krieger Publishing Company where it is reported that stilbite has atypical silica/alumina mole ratio of 5.2. TNU-10 is reported in Hong etal., J. AM. CHEM. SOC. 2004, 126, 5817-5826 as having a silica/aluminamole ratio of about 14. When attempts were made to increase thesilica/alumina mole ratio in the product, materials other than TNU-10were produced.

In accordance with the present invention there is provided a process forconverting hydrocarbons comprising contacting a hydrocarbonaceous feedat hydrocarbon converting conditions with a catalyst comprising acrystalline molecular sieve having STI topology and having a mole ratioof at least 15 of (1) an oxide of a first tetravalent element to (2) anoxide of a trivalent element, pentavalent element, second tetravalentelement which is different from said first tetravalent element ormixture thereof. SSZ-75 has, after calcination, the X-ray diffractionlines of Table II. It should be noted that the phrase “mole ratio of atleast 15” includes the case where there is no oxide (2), i.e., the moleratio of oxide (1) to oxide (2) is infinity. In that case the molecularsieve is comprised of essentially all silicon oxide. The molecular sievemay be predominantly in the hydrogen form. It may also be substantiallyfree of acidity.

Further provided by the present invention is a hydrocracking processcomprising contacting a hydrocarbon feedstock under hydrocrackingconditions with a catalyst comprising the molecular sieve of thisinvention, preferably predominantly in the hydrogen form.

Also included in this invention is a process for increasing the octaneof a hydrocarbon feedstock to produce a product having an increasedaromatics content comprising contacting a hydrocarbonaceous feedstockwhich comprises normal and slightly branched hydrocarbons having aboiling range above about 40° C. and less than about 200° C., underaromatic conversion conditions with a catalyst comprising the molecularsieve of this invention made substantially free of acidity byneutralizing said molecular sieve with a basic metal. Also provided inthis invention is such a process wherein the molecular sieve contains aGroup VIII metal component.

Also provided by the present invention is a catalytic cracking processcomprising contacting a hydrocarbon feedstock in a reaction zone undercatalytic cracking conditions in the absence of added hydrogen with acatalyst comprising the molecular sieve of this invention, preferablypredominantly in the hydrogen form. Also included in this invention issuch a catalytic cracking process wherein the catalyst additionallycomprises a large pore crystalline cracking component.

This invention further provides an isomerization process for isomerizingC₄ to C₇ hydrocarbons, comprising contacting a feed having normal andslightly branched C₄ to C₇ hydrocarbons under isomerizing conditionswith a catalyst comprising the molecular sieve of this invention,preferably predominantly in the hydrogen form. The molecular sieve maybe impregnated with at least one Group VIII metal, preferably platinum.The catalyst may be calcined in a steam/air mixture at an elevatedtemperature after impregnation of the Group VIII metal.

Also provided by the present invention is a process for alkylating anaromatic hydrocarbon which comprises contacting under alkylationconditions at least a molar excess of an aromatic hydrocarbon with a C₂to C₂₀ olefin under at least partial liquid phase conditions and in thepresence of a catalyst comprising the molecular sieve of this invention,preferably predominantly in the hydrogen form. The olefin may be a C₂ toC₄ olefin, and the aromatic hydrocarbon and olefin may be present in amolar ratio of about 4:1 to about 20:1, respectively. The aromatichydrocarbon may be selected from the group consisting of benzene,toluene, ethylbenzene, xylene, naphthalene, naphthalene derivatives,dimethylnaphthalene or mixtures thereof.

Further provided in accordance with this invention is a process fortransalkylating an aromatic hydrocarbon which comprises contacting undertransalkylating conditions an aromatic hydrocarbon with a polyalkylaromatic hydrocarbon under at least partial liquid phase conditions andin the presence of a catalyst comprising the molecular sieve of thisinvention, preferably predominantly in the hydrogen form. The aromatichydrocarbon and the polyalkyl aromatic hydrocarbon may be present in amolar ratio of from about 1:1 to about 25:1, respectively.

The aromatic hydrocarbon may be selected from the group consisting ofbenzene, toluene, ethylbenzene, xylene, or mixtures thereof, and thepolyalkyl aromatic hydrocarbon may be a dialkylbenzene.

Further provided by this invention is a process to convert paraffins toaromatics which comprises contacting paraffins under conditions whichcause paraffins to convert to aromatics with a catalyst comprising themolecular sieve of this invention, said catalyst comprising gallium,zinc, or a compound of gallium or zinc.

In accordance with this invention there is also provided a process forisomerizing olefins comprising contacting said olefin under conditionswhich cause isomerization of the olefin with a catalyst comprising themolecular sieve of this invention.

Further provided in accordance with this invention is a process forisomerizing an isomerization feed comprising an aromatic C₈ stream ofxylene isomers or mixtures of xylene isomers and ethylbenzene, wherein amore nearly equilibrium ratio of ortho-, meta- and para-xylenes isobtained, said process comprising contacting said feed underisomerization conditions with a catalyst comprising the molecular sieveof this invention.

The present invention further provides a process for oligomerizingolefins comprising contacting an olefin feed under oligomerizationconditions with a catalyst comprising the molecular sieve of thisinvention.

This invention also provides a process for converting oxygenatedhydrocarbons comprising contacting said oxygenated hydrocarbon with acatalyst comprising the molecular sieve of this invention underconditions to produce liquid products. The oxygenated hydrocarbon may bea lower alcohol.

Further provided in accordance with the present invention is a processfor the production of higher molecular weight hydrocarbons from lowermolecular weight hydrocarbons comprising the steps of:

-   -   (a) introducing into a reaction zone a lower molecular weight        hydrocarbon-containing gas and contacting said gas in said zone        under C₂₊ hydrocarbon synthesis conditions with the catalyst and        a metal or metal compound capable of converting the lower        molecular weight hydrocarbon to a higher molecular weight        hydrocarbon; and    -   (b) withdrawing from said reaction zone a higher molecular        weight hydrocarbon-containing stream.

The present invention further provides a process for hydrogenating ahydrocarbon feed containing unsaturated hydrocarbons, the processcomprising contacting the feed and hydrogen under conditions which causehydrogenation with a catalyst comprising the molecular sieve of thisinvention. The catalyst can also contain metals, salts or complexeswherein the metal is selected from the group consisting of platinum,palladium, rhodium, iridium or combinations thereof, or the groupconsisting of nickel, molybdenum, cobalt, tungsten, titanium, chromium,vanadium, rhenium, manganese and combinations thereof.

The present invention also provides a catalyst composition for promotingpolymerization of 1-olefins, said composition comprising

-   -   (a) a crystalline molecular sieve having a mole ratio of at        least 15 of (1) an oxide of a first tetravalent element to (2)        an oxide of a trivalent element, pentavalent element, second        tetravalent element which is different from said first        tetravalent element or mixture thereof and having, after        calcination, the X-ray diffraction lines of Table II; and    -   (b) an organotitanium or organochromium compound.

Also provided is a process for polymerizing 1-olefins, which processcomprises contacting 1-olefin monomer with a catalytically effectiveamount of a catalyst composition comprising

-   -   (a) a crystalline molecular sieve having a mole ratio of at        least 15 of (1) an oxide of a first tetravalent element to (2)        an oxide of a trivalent element, pentavalent element, second        tetravalent element which is different from said first        tetravalent element or mixture thereof and having, after        calcination, the X-ray diffraction lines of Table II; and    -   (b) an organotitanium or organochromium compound.        under polymerization conditions which include a temperature and        pressure suitable for initiating and promoting the        polymerization reaction. The 1-olefin may be ethylene.

The present invention further provides a dewaxing process comprisingcontacting a hydrocarbon feedstock under dewaxing conditions with acatalyst comprising a crystalline molecular sieve having STI topologyand a mole ratio of at least about 14 of (1) an oxide of a firsttetravalent element to (2) an oxide of a trivalent element, pentavalentelement, second tetravalent element which is different from said firsttetravalent element or mixture thereof. The molecular sieve ispreferably predominantly in the hydrogen form.

Also provided is a process for improving the viscosity index of adewaxed product of waxy hydrocarbon feeds comprising contacting a waxyhydrocarbon feed under isomerization dewaxing conditions with a catalystcomprising a crystalline molecular sieve having STI topology and a moleratio of at least about 14 of (1) an oxide of a first tetravalentelement to (2) an oxide of a trivalent element, pentavalent element,second tetravalent element which is different from said firsttetravalent element or mixture thereof. The molecular sieve ispreferably predominantly in the hydrogen form.

Further provided by the present invention is a process for producing aC₂₀₊ lube oil from a C₂₀₊ olefin feed comprising isomerizing said olefinfeed under isomerization conditions over a catalyst comprising acrystalline molecular sieve having STI topology and a mole ratio of atleast about 14 of (1) an oxide of a first tetravalent element to (2) anoxide of a trivalent element, pentavalent element, second tetravalentelement which is different from said first tetravalent element ormixture thereof. The molecular sieve may be predominantly in thehydrogen form. The catalyst may contain at least one Group VIII metal.

Also provided is a process for catalytically dewaxing a hydrocarbon oilfeedstock boiling above about 350° F. (177° C.) and containing straightchain and slightly branched chain hydrocarbons comprising contactingsaid hydrocarbon oil feedstock in the presence of added hydrogen gas ata hydrogen pressure of about 15-3000 psi (0.103-20.7 MPa) under dewaxingconditions with a catalyst comprising a crystalline molecular sievehaving STI topology and a mole ratio of at least about 14 of (1) anoxide of a first tetravalent element to (2) an oxide of a trivalentelement, pentavalent element, second tetravalent element which isdifferent from said first tetravalent element or mixture thereof. Themolecular sieve may be predominantly in the hydrogen form. The catalystmay contain at least one Group VIII metal. The catalyst may comprise acombination comprising a first catalyst comprising the molecular sieveand at least one Group VIII metal, and a second catalyst comprising analuminosilicate zeolite which is more shape selective than the molecularsieve of said first catalyst.

The present invention further provides a process for preparing alubricating oil which comprises:

hydrocracking in a hydrocracking zone a hydrocarbonaceous feedstock toobtain an effluent comprising a hydrocracked oil; andcatalytically dewaxing said effluent comprising hydrocracked oil at atemperature of at least about 400° F. (204° C.) and at a pressure offrom about 15 psig to about 3000 psig (0.103 to 20.7 MPa gauge) in thepresence of added hydrogen gas with a catalyst comprising a crystallinemolecular sieve having STI topology and a mole ratio of at least about14 of (1) an oxide of a first tetravalent element to (2) an oxide of atrivalent element, pentavalent element, second tetravalent element whichis different from said first tetravalent element or mixture thereof. Themolecular sieve may be predominantly in the hydrogen form. The catalystmay contain at least one Group VIII metal.

Also provided is a process for isomerization dewaxing a raffinatecomprising contacting said raffinate in the presence of added hydrogenunder isomerization dewaxing conditions with a catalyst comprising acrystalline molecular sieve having STI topology and a mole ratio of atleast about 14 of (1) an oxide of a first tetravalent element to (2) anoxide of a trivalent element, pentavalent element, second tetravalentelement which is different from said first tetravalent element ormixture thereof. The raffinate may be bright stock, and the molecularsieve may be predominantly in the hydrogen form. The catalyst maycontain at least one Group VIII metal.

DETAILED DESCRIPTION OF THE INVENTION

The present invention comprises a molecular sieve designated herein“molecular sieve SSZ-75” or simply “SSZ-75”.

In preparing SSZ-75, a tetramethylene-1,4-bis-(N-methylpyrrolidinium)dication is used as a structure directing agent (“SDA”), also known as acrystallization template. The SDA useful for making SSZ-75 has thefollowing structure:

The SDA dication is associated with anions (X⁻) which may be any anionthat is not detrimental to the formation of the SSZ-75. Representativeanions include halogen, e.g., fluoride, chloride, bromide and iodide,hydroxide, acetate, sulfate, tetrafluoroborate, carboxylate, and thelike. Hydroxide is the most preferred anion. The structure directingagent (SDA) may be used to provide hydroxide ion. Thus, it is beneficialto ion exchange, for example, a halide to hydroxide ion.

The tetramethylene-1,4-bis-(N-methylpyrrolidinium) dication SDA can beprepared by a method similar to that described in U.S. Pat. No.5,166,111, issued Nov. 24, 1992 to Zones et al., which discloses amethod for preparing a bis(1,4-diazoniabicyclo[2.2.2]alpha, omega alkanecompound, or U.S. Pat. No. 5,268,161, issued Dec. 7, 1993, whichdiscloses a method for preparing1,3,3,8,8-pentamethyl-3-azoniabicyclo[3.2.1]octane cation. U.S. Pat. No.5,166,111 and U.S. Pat. No. 5,268,161 are incorporated by referenceherein in their entirety.

In general, SSZ-75 is prepared by contacting (1) an active source(s) ofsilicon oxide, and (2) an active source(s) of aluminum oxide, galliumoxide, iron oxide, boron oxide, titanium oxide, indium oxide andmixtures thereof with the tetramethylene-1,4-bis-(N-methylpyrrolidinium)dication SDA in the presence of fluoride ion.

SSZ-75 is prepared from a reaction mixture comprising, in terms of moleratios, the following:

TABLE A Reaction Mixture SiO₂/X_(a)O_(b) ≧15 (i.e., 15-infinity)OH—/SiO₂ 0.20-0.80 Q/SiO₂ 0.20-0.80 M_(2/n)/SiO₂   0-0.04 H₂O/SiO₂  2-10HF/SiO₂ 0.20-0.80where X is aluminum, gallium, iron, boron, titanium, indium and mixturesthereof, a is 1 or 2, b is 2 when a is 1 (i.e., W is tetravalent); b is3 when a is 2 (i.e., W is trivalent), M is an alkali metal cation,alkaline earth metal cation or mixtures thereof; n is the valence of M(i.e., 1 or 2); Q is a tetramethylene-1,4-bis-(N-methylpyrrolidinium)dication and F is fluoride.

As noted above, the SiO₂/X_(a)O_(b) mole ratio in the reaction mixtureis ≧15. This means that the SiO₂/X_(a)O_(b) mole ratio can be infinity,i.e., there is no X_(a)O_(b) in the reaction mixture. This results in aversion of SSZ-75 that is essentially all silica. As used herein,“essentially all silicon oxide” or “essentially all-silica” means thatthe molecular sieve's crystal structure is comprised of only siliconoxide or is comprised of silicon oxide and only trace amounts of otheroxides, such as aluminum oxide, which may be introduced as impurities inthe source of silicon oxide.

In practice, SSZ-75 is prepared by a process comprising:

-   -   (a) preparing an aqueous solution containing (1) a source(s) of        silicon oxide, (2) a source(s) of aluminum oxide, gallium oxide,        iron oxide, boron oxide, titanium oxide, indium oxide and        mixtures thereof, (3) a source of fluoride ion and (4) a        tetramethylene-1,4-bis-(N-methylpyrrolidinium) dication having        an anionic counterion which is not detrimental to the formation        of SSZ-75;    -   (b) maintaining the aqueous solution under conditions sufficient        to form crystals of SSZ-75; and    -   (c) recovering the crystals of SSZ-75.

The reaction mixture is maintained at an elevated temperature until thecrystals of the SSZ-75 are formed. The hydrothermal crystallization isusually conducted under autogenous pressure, at a temperature between100° C. and 200° C., preferably between 135° C. and 180° C. Thecrystallization period is typically greater than 1 day and preferablyfrom about 3 days to about 20 days. The molecular sieve may be preparedusing mild stirring or agitation.

During the hydrothermal crystallization step, the SSZ-75 crystals can beallowed to nucleate spontaneously from the reaction mixture. The use ofSSZ-75 crystals as seed material can be advantageous in decreasing thetime necessary for complete crystallization to occur. In addition,seeding can lead to an increased purity of the product obtained bypromoting the nucleation and/or formation of SSZ-75 over any undesiredphases. When used as seeds, SSZ-75 crystals are added in an amountbetween 0.1 and 10% of the weight of the first tetravalent elementoxide, e.g. silica, used in the reaction mixture.

Once the molecular sieve crystals have formed, the solid product isseparated from the reaction mixture by standard mechanical separationtechniques such as filtration. The crystals are water-washed and thendried, e.g., at 90° C. to 150° C. for from 8 to 24 hours, to obtain theas-synthesized SSZ-75 crystals. The drying step can be performed atatmospheric pressure or under vacuum.

SSZ-75 as prepared has the X-ray diffraction lines of Table I below.SSZ-75 has a composition, as synthesized (i.e., prior to removal of theSDA from the SSZ-75) and in the anhydrous state, comprising thefollowing (in terms of mole ratios):

SiO₂/X_(c)O_(d) at least 15 (i.e., 15-infinity) M_(2/n)/SiO₂   0-0.03Q/SiO₂ 0.02-0.08 F/SiO₂ 0.01-0.04wherein X is aluminum, gallium, iron, boron, titanium, indium andmixtures thereof, c is 1 or 2; d is 2 when c is 1 (i.e., W istetravalent) or d is 3 or 5 when c is 2 (i.e., d is 3 when W istrivalent or 5 when W is pentavalent), M is an alkali metal cation,alkaline earth metal cation or mixtures thereof; n is the valence of M(i.e., 1 or 2); Q is a tetramethylene-1,4-bis-(N-methyl-pyrrolidinium)dication and F is fluoride.

SSZ-75 (whether in the as synthesized or calcined version) has aSiO₂/X_(c)O_(d) mole ratio of ≧15 (i.e., 15-infinity), for example20-infinity or 40-infinity.

SSZ-75 is characterized by its X-ray diffraction pattern. SSZ-75,as-synthesized, has a crystalline structure whose X-ray powderdiffraction pattern exhibits the characteristic lines shown in Table I.

TABLE I As-Synthesized SSZ-75 Relative Integrated 2 Theta d-spacing(Angstroms) Intensity (%) 10.04 8.80 VS 17.17 5.16 W 19.44 4.56 S 21.134.20 W-M 22.36 3.97 VS 22.49 3.95 M 24.19 3.68 W 26.61 3.35 W 28.49 3.13W 30.20 2.96 M ^((a))±0.1 ^((b))The X-ray patterns provided are based ona relative intensity scale in which the strongest line in the X-raypattern is assigned a value of 100: W(weak) is less than 20; M(medium)is between 20 and 40; S(strong) is between 40 and 60; VS(very strong) isgreater than 60.

Table IA below shows the X-ray powder diffraction lines foras-synthesized SSZ-75 including actual relative intensities.

TABLE IA As-Synthesized SSZ-75 Relative Integrated 2 Theta d-spacing(Angstroms) Intensity (%) 9.84 8.98 7 10.04 8.80 100 13.24 6.68 7 14.196.24 4 17.17 5.16 13 19.44 4.56 47 20.01 4.43 2 20.17 4.40 7 21.13 4.2021 22.36 3.97 84 22.49 3.95 38 24.19 3.68 12 26.13 3.41 7 26.61 3.35 1728.49 3.13 18 29.31 3.04 10 30.20 2.96 30 30.30 2.95 7 31.94 2.80 232.12 2.78 1 32.61 2.74 3 33.13 2.70 4 33.59 2.67 6 34.86 2.57 7 35.132.55 5 35.75 2.51 6 36.55 2.46 2 36.69 2.45 1 37.19 2.42 1 ^((a))±0.1

After calcination, the X-ray powder diffraction pattern for SSZ-75exhibits the characteristic lines shown in Table II below.

TABLE II Calcined SSZ-75 Relative Integrated 2 Theta d-spacing(Angstroms) Intensity (%) 9.64 9.17 W 9.95 8.88 VS 10.06 8.79 M 13.146.73 W 19.38 4.58 W 21.03 4.22 W 22.35 3.97 M-S 24.19 3.68 W 28.37 3.14W 30.16 2.96 W ^((a))±0.1

Table IIA below shows the X-ray powder diffraction lines for calcinedSSZ-75 including actual relative intensities.

TABLE IIA Calcined SSZ-75 Relative Integrated Intensity 2 Thetad-spacing (Angstroms) (%) 9.64 9.17 8 9.95 8.88 100 10.06 8.79 24 13.146.73 7 14.17 6.25 2 17.13 5.17 2 17.25 5.14 3 19.38 4.58 15 20.23 4.39 121.03 4.22 10 22.35 3.97 39 22.54 3.94 6 24.19 3.68 7 25.24 3.53 6 26.083.41 2 26.48 3.36 6 28.37 3.14 7 29.25 3.05 3 30.16 2.96 13 30.32 2.95 232.18 2.78 1 33.02 2.71 2 33.54 2.67 2 34.57 2.59 1 34.94 2.57 2 35.092.56 1 35.68 2.51 2 36.58 2.45 1 37.07 2.42 1 ^((a))±0.1

The X-ray powder diffraction patterns were determined by standardtechniques. The radiation was CuKalpha radiation. The peak heights andthe positions, as a function of 2θ where θ is the Bragg angle, were readfrom the relative intensities of the peaks, and d, the interplanarspacing in Angstroms corresponding to the recorded lines, can becalculated.

The variation in the scattering angle (two theta) measurements, due toinstrument error and to differences between individual samples, isestimated at ±0.1 degrees.

Representative peaks from the X-ray diffraction pattern of calcinedSSZ-75 are shown in Table I. Calcination can result in changes in theintensities of the peaks as compared to patterns of the “as-made”material, as well as minor shifts in the diffraction pattern.

Crystalline SSZ-75 can be used as-synthesized, but preferably will bethermally treated (calcined). Usually, it is desirable to remove thealkali metal cation (if any) by ion exchange and replace it withhydrogen, ammonium, or any desired metal ion.

SSZ-75 can be formed into a wide variety of physical shapes. Generallyspeaking, the molecular sieve can be in the form of a powder, a granule,or a molded product, such as extrudate having a particle size sufficientto pass through a 2-mesh (Tyler) screen and be retained on a 400-mesh(Tyler) screen. In cases where the catalyst is molded, such as byextrusion with an organic binder, the SSZ-75 can be extruded beforedrying, or, dried or partially dried and then extruded.

SSZ-75 can be composited with other materials resistant to thetemperatures and other conditions employed in organic conversionprocesses. Such matrix materials include active and inactive materialsand synthetic or naturally occurring zeolites as well as inorganicmaterials such as clays, silica and metal oxides. Examples of suchmaterials and the manner in which they can be used are disclosed in U.S.Pat. No. 4,910,006, issued May 20, 1990 to Zones et al., and U.S. Pat.No. 5,316,753, issued May 31, 1994 to Nakagawa, both of which areincorporated by reference herein in their entirety.

Hydrocarbon Conversion Processes

SSZ-75 molecular sieves are useful in hydrocarbon conversion reactions.Hydrocarbon conversion reactions are chemical and catalytic processes inwhich carbon containing compounds are changed to different carboncontaining compounds. Examples of hydrocarbon conversion reactions inwhich SSZ-75 is expected to be useful include hydrocracking, dewaxing,catalytic cracking and olefin and aromatics formation reactions. Thecatalysts are also expected to be useful in other petroleum refining andhydrocarbon conversion reactions such as isomerizing n-paraffins andnaphthenes, polymerizing and oligomerizing olefinic or acetyleniccompounds such as isobutylene and butene-1, polymerization of 1-olefins(e.g., ethylene), reforming, isomerizing polyalkyl substituted aromatics(e.g., m-xylene), and disproportionating aromatics (e.g., toluene) toprovide mixtures of benzene, xylenes and higher methylbenzenes andoxidation reactions. Also included are rearrangement reactions to makevarious naphthalene derivatives, and forming higher molecular weighthydrocarbons from lower molecular weight hydrocarbons (e.g., methaneupgrading).

The SSZ-75 catalysts may have high selectivity, and under hydrocarbonconversion conditions can provide a high percentage of desired productsrelative to total products.

For high catalytic activity, the SSZ-75 molecular sieve should bepredominantly in its hydrogen ion form. Generally, the molecular sieveis converted to its hydrogen form by ammonium exchange followed bycalcination. If the molecular sieve is synthesized with a high enoughratio of SDA cation to sodium ion, calcination alone may be sufficient.It is preferred that, after calcination, at least 80% of the cationsites are occupied by hydrogen ions and/or rare earth ions. As usedherein, “predominantly in the hydrogen form” means that, aftercalcination, at least 80% of the cation sites are occupied by hydrogenions and/or rare earth ions.

SSZ-75 molecular sieves can be used in processing hydrocarbonaceousfeedstocks. Hydrocarbonaceous feedstocks contain carbon compounds andcan be from many different sources, such as virgin petroleum fractions,recycle petroleum fractions, shale oil, liquefied coal, tar sand oil,synthetic paraffins from NAO, recycled plastic feedstocks. Other feedsinclude synthetic feeds, such as those derived from a Fischer Tropschprocess, including an oxygenate-containing Fischer Tropsch processboiling below about 371° C. (700° F.). In general, the feed can be anycarbon containing feedstock susceptible to zeolitic catalytic reactions.Depending on the type of processing the hydrocarbonaceous feed is toundergo, the feed can contain metal or be free of metals, it can alsohave high or low nitrogen or sulfur impurities. It can be appreciated,however, that in general processing will be more efficient (and thecatalyst more active) the lower the metal, nitrogen, and sulfur contentof the feedstock.

The conversion of hydrocarbonaceous feeds can take place in anyconvenient mode, for example, in fluidized bed, moving bed, or fixed bedreactors depending on the types of process desired. The formulation ofthe catalyst particles will vary depending on the conversion process andmethod of operation.

Other reactions which can be performed using the catalyst of thisinvention containing a metal, e.g., a Group VIII metal such platinum,include hydrogenation-dehydrogenation reactions, denitrogenation anddesulfurization reactions.

The following table indicates typical reaction conditions which may beemployed when using catalysts comprising SSZ-75 in the hydrocarbonconversion reactions of this invention. Preferred conditions areindicated in parentheses.

Process Temp., ° C. Pressure LHSV Hydrocracking 175-485 0.5-350 bar0.1-30 Dewaxing 200-475 15-3000 psig, 0.1-20 (250-450) 0.103-20.7 Mpa(0.2-10) gauge (200-3000, 1.38-20.7 Mpa gauge) Aromatics 400-600 atm.-10bar 0.1-15 formation (480-550) Cat. Cracking 127-885 subatm.-¹ 0.5-50(atm.-5 atm.) Oligomerization  232-649² 0.1-50 atm.^(2,3)  0.2-50² 10-232⁴ —  0.05-20⁵   (27-204)⁴ —  (0.1-10)⁵ Paraffins to 100-7000-1000 psig  0.5-40⁵ aromatics Condensation 260-538 0.5-1000 psig, 0.5-50⁵ of alcohols 0.00345-6.89 Mpa gauge Isomerization  93-53850-1000 psig,   1-10 (204-315) 0.345-6.89 Mpa gauge  (1-4) Xylene 260-593² 0.5-50 atm.²   0.1-100⁵ isomerization  (315-566)² (1-5 atm)² (0.5-50)⁵   38-371⁴ 1-200 atm.⁴ 0.5-50 ¹Several hundred atmospheres²Gas phase reaction ³Hydrocarbon partial pressure ⁴Liquid phase reaction⁵WHSVOther reaction conditions and parameters are provided below.

Hydrocracking

Using a catalyst which comprises SSZ-75, preferably predominantly in thehydrogen form, and a hydrogenation promoter, heavy petroleum residualfeedstocks, cyclic stocks and other hydrocrackate charge stocks can behydrocracked using the process conditions and catalyst componentsdisclosed in the aforementioned U.S. Pat. No. 4,910,006 and U.S. Pat.No. 5,316,753.

The hydrocracking catalysts contain an effective amount of at least onehydrogenation component of the type commonly employed in hydrocrackingcatalysts. The hydrogenation component is generally selected from thegroup of hydrogenation catalysts consisting of one or more metals ofGroup VIB and Group VIII, including the salts, complexes and solutionscontaining such. The hydrogenation catalyst is preferably selected fromthe group of metals, salts and complexes thereof of the group consistingof at least one of platinum, palladium, rhodium, iridium, ruthenium andmixtures thereof or the group consisting of at least one of nickel,molybdenum, cobalt, tungsten, titanium, chromium and mixtures thereof.Reference to the catalytically active metal or metals is intended toencompass such metal or metals in the elemental state or in some formsuch as an oxide, sulfide, halide, carboxylate and the like. Thehydrogenation catalyst is present in an effective amount to provide thehydrogenation function of the hydrocracking catalyst, and preferably inthe range of from 0.05 to 25% by weight.

Dewaxing

For dewaxing processes, the catalyst comprises a molecular sieve havingSTI topology and having a mole ratio of at least 15 of (1) an oxide of afirst tetravalent element to (2) an oxide of a trivalent element,pentavalent element, second tetravalent element which is different fromsaid first tetravalent element or mixture thereof. Thus, the molecularsieve may be SSZ-75 or TNU-10, preferably predominantly in the hydrogenform. The catalyst can be used to dewax hydrocarbonaceous feeds byselectively removing straight chain paraffins. Typically, the viscosityindex of the dewaxed product is improved (compared to the waxy feed)when the waxy feed is contacted with SSZ-75 or TNU-10 underisomerization dewaxing conditions.

The catalytic dewaxing conditions are dependent in large measure on thefeed used and upon the desired pour point. Hydrogen is preferablypresent in the reaction zone during the catalytic dewaxing process. Thehydrogen to feed ratio is typically between about 500 and about 30,000SCF/bbl (standard cubic feet per barrel) (0.089 to 5.34 SCM/liter(standard cubic meters/liter)), preferably about 1000 to about 20,000SCF/bbl (0.178 to 3.56 SCM/liter). Generally, hydrogen will be separatedfrom the product and recycled to the reaction zone. Typical feedstocksinclude light gas oil, heavy gas oils and reduced crudes boiling aboveabout 350° F. (177° C.).

A typical dewaxing process is the catalytic dewaxing of a hydrocarbonoil feedstock boiling above about 350° F. (177° C.) and containingstraight chain and slightly branched chain hydrocarbons by contactingthe hydrocarbon oil feedstock in the presence of added hydrogen gas at ahydrogen pressure of about 15-3000 psi (0.103-20.7 Mpa) with a catalystcomprising SSZ-75 and at least one Group VIII metal.

The SSZ-75 or TNU-10 hydrodewaxing catalyst may optionally contain ahydrogenation component of the type commonly employed in dewaxingcatalysts. See the aforementioned U.S. Pat. No. 4,910,006 and U.S. Pat.No. 5,316,753 for examples of these hydrogenation components.

The hydrogenation component is present in an effective amount to providean effective hydrodewaxing and hydroisomerization catalyst preferably inthe range of from about 0.05 to 5% by weight. The catalyst may be run insuch a mode to increase isomerization dewaxing at the expense ofcracking reactions.

The feed may be hydrocracked, followed by dewaxing. This type of twostage process and typical hydrocracking conditions are described in U.S.Pat. No. 4,921,594, issued May 1, 1990 to Miller, which is incorporatedherein by reference in its entirety.

SSZ-75 or TNU-10 may also be utilized as a combination of catalysts.That is, the catalyst comprises a combination comprising molecular sieveSSZ-75 or TNU-10 and at least one Group VIII metal, and a secondcatalyst comprising an aluminosilicate zeolite which is more shapeselective than molecular sieve SSZ-75 or TNU-10. The combination may becomprised of layers. The use of layered catalysts is disclosed in U.S.Pat. No. 5,149,421, issued Sep. 22, 1992 to Miller, which isincorporated by reference herein in its entirety. The layering may alsoinclude a bed of SSZ-75 or TNU=10 layered with a non-zeolitic componentdesigned for either hydrocracking or hydrofinishing.

SSZ-75 or TNU-10 may also be used to dewax raffinates, including brightstock, under conditions such as those disclosed in U.S. Pat. No.4,181,598, issued Jan. 1, 1980 to Gillespie et al., which isincorporated by reference herein in its entirety.

It is often desirable to use mild hydrogenation (sometimes referred toas hydrofinishing) to produce more stable dewaxed products. Thehydrofinishing step can be performed either before or after the dewaxingstep, and preferably after. Hydrofinishing is typically conducted attemperatures ranging from about 190° C. to about 340° C. at pressuresfrom about 400 psig to about 3000 psig (2.76 to 20.7 Mpa gauge) at spacevelocities (LHSV) between about 0.1 and 20 and a hydrogen recycle rateof about 400 to 1500 SCF/bbl (0.071 to 0.27 SCM/liter). Thehydrogenation catalyst employed must be active enough not only tohydrogenate the olefins, diolefins and color bodies which may bepresent, but also to reduce the aromatic content. Suitable hydrogenationcatalyst are disclosed in U.S. Pat. No. 4,921,594, issued May 1, 1990 toMiller, which is incorporated by reference herein in its entirety. Thehydrofinishing step is beneficial in preparing an acceptably stableproduct (e.g., a lubricating oil) since dewaxed products prepared fromhydrocracked stocks tend to be unstable to air and light and tend toform sludges spontaneously and quickly.

Lube oil may be prepared using SSZ-75 or TNU-10. For example, a C₂₀₊lube oil may be made by isomerizing a C₂₀₊ olefin feed over a catalystcomprising SSZ-75 or TNU-10 in the hydrogen form and at least one GroupVIII metal. Alternatively, the lubricating oil may be made byhydrocracking in a hydrocracking zone a hydrocarbonaceous feedstock toobtain an effluent comprising a hydrocracked oil, and catalyticallydewaxing the effluent at a temperature of at least about 400° F. (204°C.) and at a pressure of from about 15 psig to about 3000 psig(0.103-20.7 Mpa gauge) in the presence of added hydrogen gas with acatalyst comprising SSZ-75 or TNU-10F in the hydrogen form and at leastone Group VIII metal.

Aromatics Formation

SSZ-75 can be used to convert light straight run naphthas and similarmixtures to highly aromatic mixtures. Thus, normal and slightly branchedchained hydrocarbons, preferably having a boiling range above about 40°C. and less than about 200° C., can be converted to products having asubstantial higher octane aromatics content by contacting thehydrocarbon feed with a catalyst comprising SSZ-75. It is also possibleto convert heavier feeds into BTX or naphthalene derivatives of valueusing a catalyst comprising SSZ-75.

The conversion catalyst preferably contains a Group VIII metal compoundto have sufficient activity for commercial use. By Group VIII metalcompound as used herein is meant the metal itself or a compound thereof.The Group VIII noble metals and their compounds, platinum, palladium,and iridium, or combinations thereof can be used. Rhenium or tin or amixture thereof may also be used in conjunction with the Group VIIImetal compound and preferably a noble metal compound. The most preferredmetal is platinum. The amount of Group VIII metal present in theconversion catalyst should be within the normal range of use inreforming catalysts, from about 0.05 to 2.0 weight percent, preferably0.2 to 0.8 weight percent.

It is critical to the selective production of aromatics in usefulquantities that the conversion catalyst be substantially free ofacidity, for example, by neutralizing the molecular sieve with a basicmetal, e.g., alkali metal, compound. Methods for rendering the catalystfree of acidity are known in the art. See the aforementioned U.S. Pat.No. 4,910,006 and U.S. Pat. No. 5,316,753 for a description of suchmethods.

The preferred alkali metals are sodium, potassium, rubidium and cesium.The molecular sieve itself can be substantially free of acidity only atvery high silica:alumina mole ratios.

Catalytic Cracking

Hydrocarbon cracking stocks can be catalytically cracked in the absenceof hydrogen using SSZ-75, preferably predominantly in the hydrogen form.

When SSZ-75 is used as a catalytic cracking catalyst in the absence ofhydrogen, the catalyst may be employed in conjunction with traditionalcracking catalysts, e.g., any aluminosilicate heretofore employed as acomponent in cracking catalysts. Typically, these are large pore,crystalline aluminosilicates. Examples of these traditional crackingcatalysts are disclosed in the aforementioned U.S. Pat. No. 4,910,006and U.S. Pat. No. 5,316,753. When a traditional cracking catalyst (TC)component is employed, the relative weight ratio of the TC to the SSZ-75is generally between about 1:10 and about 500:1, desirably between about1:10 and about 200:1, preferably between about 1:2 and about 50:1, andmost preferably is between about 1:1 and about 20:1. The novel molecularsieve and/or the traditional cracking component may be further ionexchanged with rare earth ions to modify selectivity.

The cracking catalysts are typically employed with an inorganic oxidematrix component. See the aforementioned U.S. Pat. No. 4,910,006 andU.S. Pat. No. 5,316,753 for examples of such matrix components.

Isomerization

The present catalyst is highly active and highly selective forisomerizing C₄ to C₇ hydrocarbons. The activity means that the catalystcan operate at relatively low temperature which thermodynamically favorshighly branched paraffins. Consequently, the catalyst can produce a highoctane product. The high selectivity means that a relatively high liquidyield can be achieved when the catalyst is run at a high octane.

The present process comprises contacting the isomerization catalyst,i.e., a catalyst comprising SSZ-75 in the hydrogen form, with ahydrocarbon feed under isomerization conditions. The feed is preferablya light straight run fraction, boiling within the range of 30° F. to250° F. (−1° C. to 121° C.) and preferably from 60° F. to 200° F. (16°C. to 93° C.). Preferably, the hydrocarbon feed for the processcomprises a substantial amount of C₄ to C₇ normal and slightly branchedlow octane hydrocarbons, more preferably C₅ and C₆ hydrocarbons.

It is preferable to carry out the isomerization reaction in the presenceof hydrogen. Preferably, hydrogen is added to give a hydrogen tohydrocarbon ratio (H₂/HC) of between 0.5 and 10H₂/HC, more preferablybetween 1 and 8H₂/HC. See the aforementioned U.S. Pat. No. 4,910,006 andU.S. Pat. No. 5,316,753 for a further discussion of isomerizationprocess conditions.

A low sulfur feed is especially preferred in the present process. Thefeed preferably contains less than 10 ppm, more preferably less than 1ppm, and most preferably less than 0.1 ppm sulfur. In the case of a feedwhich is not already low in sulfur, acceptable levels can be reached byhydrogenating the feed in a presaturation zone with a hydrogenatingcatalyst which is resistant to sulfur poisoning. See the aforementionedU.S. Pat. No. 4,910,006 and U.S. Pat. No. 5,316,753 for a furtherdiscussion of this hydrodesulfurization process.

It is preferable to limit the nitrogen level and the water content ofthe feed. Catalysts and processes which are suitable for these purposesare known to those skilled in the art.

After a period of operation, the catalyst can become deactivated bysulfur or coke. See the aforementioned U.S. Pat. No. 4,910,006 and U.S.Pat. No. 5,316,753 for a further discussion of methods of removing thissulfur and coke, and of regenerating the catalyst.

The conversion catalyst preferably contains a Group VIII metal compoundto have sufficient activity for commercial use. By Group VIII metalcompound as used herein is meant the metal itself or a compound thereof.The Group VIII noble metals and their compounds, platinum, palladium,and iridium, or combinations thereof can be used. Rhenium and tin mayalso be used in conjunction with the noble metal. The most preferredmetal is platinum. The amount of Group VIII metal present in theconversion catalyst should be within the normal range of use inisomerizing catalysts, from about 0.05 to 2.0 weight percent, preferably0.2 to 0.8 weight percent.

Alkylation and Transalkylation

SSZ-75 can be used in a process for the alkylation or transalkylation ofan aromatic hydrocarbon. The process comprises contacting the aromatichydrocarbon with a C₂ to C₁₆ olefin alkylating agent or a polyalkylaromatic hydrocarbon transalkylating agent, under at least partialliquid phase conditions, and in the presence of a catalyst comprisingSSZ-75.

SSZ-75 can also be used for removing benzene from gasoline by alkylatingthe benzene as described above and removing the alkylated product fromthe gasoline.

For high catalytic activity, the SSZ-75 molecular sieve should bepredominantly in its hydrogen ion form. It is preferred that, aftercalcination, at least 80% of the cation sites are occupied by hydrogenions and/or rare earth ions.

Examples of suitable aromatic hydrocarbon feedstocks which may bealkylated or transalkylated by the process of the invention includearomatic compounds such as benzene, toluene and xylene. The preferredaromatic hydrocarbon is benzene. There may be occasions wherenaphthalene or naphthalene derivatives such as dimethylnaphthalene maybe desirable. Mixtures of aromatic hydrocarbons may also be employed.

Suitable olefins for the alkylation of the aromatic hydrocarbon arethose containing 2 to 20, preferably 2 to 4, carbon atoms, such asethylene, propylene, butene-1, trans-butene-2 and cis-butene-2, ormixtures thereof. There may be instances where pentenes are desirable.The preferred olefins are ethylene and propylene. Longer chain alphaolefins may be used as well.

When transalkylation is desired, the transalkylating agent is apolyalkyl aromatic hydrocarbon containing two or more alkyl groups thateach may have from 2 to about 4 carbon atoms. For example, suitablepolyalkyl aromatic hydrocarbons include di-, tri- and tetra-alkylaromatic hydrocarbons, such as diethylbenzene, triethylbenzene,diethylmethylbenzene (diethyltoluene), di-isopropylbenzene,di-isopropyltoluene, dibutylbenzene, and the like. Preferred polyalkylaromatic hydrocarbons are the dialkyl benzenes. A particularly preferredpolyalkyl aromatic hydrocarbon is di-isopropylbenzene.

When alkylation is the process conducted, reaction conditions are asfollows. The aromatic hydrocarbon feed should be present instoichiometric excess. It is preferred that molar ratio of aromatics toolefins be greater than four-to-one to prevent rapid catalyst fouling.The reaction temperature may range from 100° F. to 600° F. (38° C. to315° C.), preferably 250° F. to 450° F. (121° C. to 232° C.). Thereaction pressure should be sufficient to maintain at least a partialliquid phase in order to retard catalyst fouling. This is typically 50psig to 1000 psig (0.345 to 6.89 Mpa gauge) depending on the feedstockand reaction temperature. Contact time may range from 10 seconds to 10hours, but is usually from 5 minutes to an hour. The weight hourly spacevelocity (WHSV), in terms of grams (pounds) of aromatic hydrocarbon andolefin per gram (pound) of catalyst per hour, is generally within therange of about 0.5 to 50.

When transalkylation is the process conducted, the molar ratio ofaromatic hydrocarbon will generally range from about 1:1 to 25:1, andpreferably from about 2:1 to 20:1. The reaction temperature may rangefrom about 100° F. to 600° F. (38° C. to 315° C.), but it is preferablyabout 250° F. to 450° F. (121° C. to 232° C.). The reaction pressureshould be sufficient to maintain at least a partial liquid phase,typically in the range of about 50 psig to 1000 psig (0.345 to 6.89 Mpagauge), preferably 300 psig to 600 psig (2.07 to 4.14 Mpa gauge). Theweight hourly space velocity will range from about 0.1 to 10. U.S. Pat.No. 5,082,990 issued on Jan. 21, 1992 to Hsieh, et al. describes suchprocesses and is incorporated herein by reference.

Conversion of Paraffins to Aromatics

SSZ-75 can be used to convert light gas C₂-C₆ paraffins to highermolecular weight hydrocarbons including aromatic compounds. Preferably,the molecular sieve will contain a catalyst metal or metal oxide whereinsaid metal is selected from the group consisting of Groups IB, IIB, VIIIand IIIA of the Periodic Table. Preferably, the metal is gallium,niobium, indium or zinc in the range of from about 0.05 to 5% by weight.

Isomerization of Olefins

SSZ-75 can be used to isomerize olefins. The feed stream is ahydrocarbon stream containing at least one C₄₋₆ olefin, preferably aC₄₋₆ normal olefin, more preferably normal butene. Normal butene as usedin this specification means all forms of normal butene, e.g., 1-butene,cis-2-butene, and trans-2-butene. Typically, hydrocarbons other thannormal butene or other C₄₋₆ normal olefins will be present in the feedstream. These other hydrocarbons may include, e.g., alkanes, otherolefins, aromatics, hydrogen, and inert gases.

The feed stream typically may be the effluent from a fluid catalyticcracking unit or a methyl-tert-butyl ether unit. A fluid catalyticcracking unit effluent typically contains about 40-60 weight percentnormal butenes. A methyl-tert-butyl ether unit effluent typicallycontains 40-100 weight percent normal butene. The feed stream preferablycontains at least about 40 weight percent normal butene, more preferablyat least about 65 weight percent normal butene. The terms iso-olefin andmethyl branched iso-olefin may be used interchangeably in thisspecification.

The process is carried out under isomerization conditions. Thehydrocarbon feed is contacted in a vapor phase with a catalystcomprising the SSZ-75. The process may be carried out generally at atemperature from about 625° F. to about 950° F. (329-510° C.), forbutenes, preferably from about 700° F. to about 900° F. (371-482° C.),and about 350° F. to about 650° F. (177-343° C.) for pentenes andhexenes. The pressure ranges from subatmospheric to about 200 psig (1.38Mpa gauge), preferably from about 15 psig to about 200 psig (0.103 to1.38 Mpa gauge), and more preferably from about 1 psig to about 150 psig(0.00689 to 1.03 Mpa gauge).

The liquid hourly space velocity during contacting is generally fromabout 0.1 to about 50 hr⁻¹, based on the hydrocarbon feed, preferablyfrom about 0.1 to about 20 hr⁻¹, more preferably from about 0.2 to about10 hr⁻¹, most preferably from about 1 to about 5 hr⁻¹. Ahydrogen/hydrocarbon molar ratio is maintained from about 0 to about 30or higher. The hydrogen can be added directly to the feed stream ordirectly to the isomerization zone. The reaction is preferablysubstantially free of water, typically less than about two weightpercent based on the feed. The process can be carried out in a packedbed reactor, a fixed bed, fluidized bed reactor, or a moving bedreactor. The bed of the catalyst can move upward or downward. The molepercent conversion of, e.g., normal butene to iso-butene is at least 10,preferably at least 25, and more preferably at least 35.

Xylene Isomerization

SSZ-75 may also be useful in a process for isomerizing one or morexylene isomers in a C₈ aromatic feed to obtain ortho-, meta-, andpara-xylene in a ratio approaching the equilibrium value. In particular,xylene isomerization is used in conjunction with a separate process tomanufacture para-xylene. For example, a portion of the para-xylene in amixed C₈ aromatics stream may be recovered by crystallization andcentrifugation. The mother liquor from the crystallizer is then reactedunder xylene isomerization conditions to restore ortho-, meta- andpara-xylenes to a near equilibrium ratio. At the same time, part of theethylbenzene in the mother liquor is converted to xylenes or to productswhich are easily separated by filtration. The isomerate is blended withfresh feed and the combined stream is distilled to remove heavy andlight by-products. The resultant C₈ aromatics stream is then sent to thecrystallizer to repeat the cycle.

Optionally, isomerization in the vapor phase is conducted in thepresence of 3.0 to 30.0 moles of hydrogen per mole of alkylbenzene(e.g., ethylbenzene). If hydrogen is used, the catalyst should compriseabout 0.1 to 2.0 wt. % of a hydrogenation/dehydrogenation componentselected from Group VIII (of the Periodic Table) metal component,especially platinum or nickel. By Group VIII metal component is meantthe metals and their compounds such as oxides and sulfides.

Optionally, the isomerization feed may contain 10 to 90 wt. of a diluentsuch as toluene, trimethylbenzene, naphthenes or paraffins.

Oligomerization

It is expected that SSZ-75 can also be used to oligomerize straight andbranched chain olefins having from about 2 to 21 and preferably 2-5carbon atoms. The oligomers which are the products of the process aremedium to heavy olefins which are useful for both fuels, i.e., gasolineor a gasoline blending stock and chemicals.

The oligomerization process comprises contacting the olefin feedstock inthe gaseous or liquid phase with a catalyst comprising SSZ-75.

The molecular sieve can have the original cations associated therewithreplaced by a wide variety of other cations according to techniques wellknown in the art. Typical cations would include hydrogen, ammonium andmetal cations including mixtures of the same. Of the replacing metalliccations, particular preference is given to cations of metals such asrare earth metals, manganese, calcium, as well as metals of Group II ofthe Periodic Table, e.g., zinc, and Group VIII of the Periodic Table,e.g., nickel. One of the prime requisites is that the molecular sievehave a fairly low aromatization activity, i.e., in which the amount ofaromatics produced is not more than about 20% by weight. This isaccomplished by using a molecular sieve with controlled acid activity[alpha value] of from about 0.1 to about 120, preferably from about 0.1to about 100, as measured by its ability to crack n-hexane.

Alpha values are defined by a standard test known in the art, e.g., asshown in U.S. Pat. No. 3,960,978 issued on Jun. 1, 1976 to Givens et al.which is incorporated totally herein by reference. If required, suchmolecular sieves may be obtained by steaming, by use in a conversionprocess or by any other method which may occur to one skilled in thisart.

Condensation of Alcohols

SSZ-75 can be used to condense lower aliphatic alcohols having 1 to 10carbon atoms to a gasoline boiling point hydrocarbon product comprisingmixed aliphatic and aromatic hydrocarbon. The process disclosed in U.S.Pat. No. 3,894,107, issued Jul. 8, 1975 to Butter et al., describes theprocess conditions used in this process, which patent is incorporatedtotally herein by reference.

The catalyst may be in the hydrogen form or may be base exchanged orimpregnated to contain ammonium or a metal cation complement, preferablyin the range of from about 0.05 to 5% by weight. The metal cations thatmay be present include any of the metals of the Groups I through VIII ofthe Periodic Table. However, in the case of Group IA metals, the cationcontent should in no case be so large as to effectively inactivate thecatalyst, nor should the exchange be such as to eliminate all acidity.There may be other processes involving treatment of oxygenatedsubstrates where a basic catalyst is desired.

Methane Upgrading

Higher molecular weight hydrocarbons can be formed from lower molecularweight hydrocarbons by contacting the lower molecular weight hydrocarbonwith a catalyst comprising SSZ-75 and a metal or metal compound capableof converting the lower molecular weight hydrocarbon to a highermolecular weight hydrocarbon. Examples of such reactions include theconversion of methane to C₂₊ hydrocarbons such as ethylene or benzene orboth. Examples of useful metals and metal compounds include lanthanideand or actinide metals or metal compounds.

These reactions, the metals or metal compounds employed and theconditions under which they can be run are disclosed in U.S. Pat. Nos.4,734,537, issued Mar. 29, 1988 to Devries et al.; 4,939,311, issuedJul. 3, 1990 to Washecheck et al.; 4,962,261, issued Oct. 9, 1990 toAbrevaya et al.; 5,095,161, issued Mar. 10, 1992 to Abrevaya et al.;5,105,044, issued Apr. 14, 1992 to Han et al.; 5,105,046, issued Apr.14, 1992 to Washecheck; 5,238,898, issued Aug. 24, 1993 to Han et al.;5,321,185, issued Jun. 14, 1994 to van der Vaart; and 5,336,825, issuedAug. 9, 1994 to Choudhary et al., each of which is incorporated hereinby reference in its entirety.

Polymerization of 1-Olefins

The molecular sieve of the present invention may be used in a catalystfor the polymerization of 1-olefins, e.g., the polymerization ofethylene. To form the olefin polymerization catalyst, the molecularsieve as hereinbefore described is reacted with a particular type oforganometallic compound. Organometallic compounds useful in forming thepolymerization catalyst include trivalent and tetravalent organotitaniumand organochromium compounds having alkyl moieties and, optionally, halomoieties. In the context of the present invention the term “alkyl”includes both straight and branched chain alkyl, cycloalkyl and alkarylgroups such as benzyl.

Examples of trivalent and tetravalent organochromium and organotitaniumcompounds are disclosed in U.S. Pat. No. 4,376,722, issued Mar. 15, 1983to Chester et al., U.S. Pat. No. 4,377,497, issued Mar. 22, 1983 toChester et al., U.S. Pat. No. 4,446,243, issued May 1, 1984 to Chesteret al., and U.S. Pat. No. 4,526,942, issued Jul. 2, 1985 to Chester etal. The disclosure of the aforementioned patents are incorporated hereinby reference in their entirety.

Examples of the organometallic compounds used to form the polymerizationcatalyst include, but are not limited to, compounds corresponding to thegeneral formula:

MY_(n)X_(m-n)

wherein M is a metal selected from titanium and chromium; Y is alkyl; Xis halogen (e.g., Cl or Br); n is 1-4; and m is greater than or equal ton and is 3 or 4.

Examples of organotitanium and organochromium compounds encompassed bysuch a formula include compounds of the formula CrY₄, CrY₃, CrY₃X,CrY₂X, CrY₂X₂, CrYX₂, CrYX₃, TiY₄, TiY₃, TiY₃X, TiY₂X, TiY₂X₂, TiYX₂,TiYX₃, wherein X can be Cl or Br and Y can be methyl, ethyl, propyl,isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl,neopentyl, hexyl, isohexyl, neohexyl, 2-ethylbutyl, octyl, 2-ethylhexyl,2,2-diethylbutyl, 2-isopropyl-3-methylbutyl, etc., cyclohexylalkyls suchas, for example, cyclohexylmethyl, 2-cyclohexylethyl,3-cyclyhexylpropyl, 4-cyclohexylbutyl, and the correspondingalkyl-substituted cyclohexyl radicals as, for example,(4-methylcyclohexyl)methyl, neophyl, i.e., beta,beta-dimethyl-phenethyl, benzyl, ethylbenzyl, and p-isopropylbenzyl.Preferred examples of Y include C₁₋₅ alkyl, especially butyl.

The organotitanium and organochromium materials employed in the catalystcan be prepared by techniques well known in the art. See, for examplethe aforementioned Chester et al. patents.

The organotitanium or organochromium compounds can be with the molecularsieve of the present invention, such as by reacting the organometalliccompound and the molecular sieve, in order to form the olefinpolymerization catalyst. Generally, such a reaction takes place in thesame reaction medium used to prepare the organometallic compound underconditions which promote formation of such a reaction product. Themolecular sieve can simply be added to the reaction mixture afterformation of the organometallic compound has been completed. Molecularsieve is added in an amount sufficient to provide from about 0.1 to 10parts by weight, preferably from about 0.5 to 5 parts by weight, oforganometallic compound in the reaction medium per 100 parts by weightof molecular sieve.

Temperature of the reaction medium during reaction of organometalliccompound with molecular sieve is also maintained at a level which is lowenough to ensure the stability of the organometallic reactant. Thus,temperatures in the range of from about −150° C. to 50° C., preferablyfrom about −80° C. to 0° C. can be usefully employed. Reaction times offrom about 0.01 to 10 hours, more preferably from about 0.1 to 1 hour,can be employed in reacting the organotitanium or organochromiumcompound with the molecular sieve.

Upon completion of the reaction, the catalyst material so formed may berecovered and dried by evaporating the reaction medium solvent under anitrogen atmosphere. Alternatively, olefin polymerization reactions canbe conducted in this same solvent based reaction medium used to form thecatalyst.

The polymerization catalyst can be used to catalyze polymerization of1-olefins. The polymers produced using the catalysts of this inventionare normally solid polymers of at least one mono-1-olefin containingfrom 2 to 8 carbon atoms per molecule. These polymers are normally solidhomopolymers of ethylene or copolymers of ethylene with anothermono-1-olefin containing 3 to 8 carbon atoms per molecule. Exemplarycopolymers include those of ethylene/propylene, ethylene/1-butene,ethylene/1-hexane, and ethylene/1-octene and the like. The major portionof such copolymers is derived from ethylene and generally consists ofabout 80-99, preferably 95-99 mole percent of ethylene. These polymersare well suited for extrusion, blow molding, injection molding and thelike.

The polymerization reaction can be conducted by contacting monomer ormonomers, e.g., ethylene, alone or with one or more other olefins, andin the substantial absence of catalyst poisons such as moisture and air,with a catalytic amount of the supported organometallic catalyst at atemperature and at a pressure sufficient to initiate the polymerizationreaction. If desired, an inert organic solvent may be used as a diluentand to facilitate materials handling if the polymerization reaction isconducted with the reactants in the liquid phase, e.g. in a particleform (slurry) or solution process. The reaction may also be conductedwith reactants in the vapor phase, e.g., in a fluidized bed arrangementin the absence of a solvent but, if desired, in the presence of an inertgas such as nitrogen.

The polymerization reaction is carried out at temperatures of from about30° C. or less, up to about 200° C. or more, depending to a great extenton the operating pressure, the pressure of the olefin monomers, and theparticular catalyst being used and its concentration. Naturally, theselected operating temperature is also dependent upon the desiredpolymer melt index since temperature is definitely a factor in adjustingthe molecular weight of the polymer. Preferably, the temperature used isfrom about 30° C. to about 100° C. in a conventional slurry or “particleforming” process or from 100° C. to 150° C. in a “solution forming”process. A temperature of from about 70° C. to 110° C. can be employedfor fluidized bed processes.

The pressure to be used in the polymerization reactions can be anypressure sufficient to initiate the polymerization of the monomer(s) tohigh molecular weight polymer. The pressure, therefore, can range fromsubatmospheric pressures, using an inert gas as diluent, tosuperatmospheric pressures of up to about 30,000 psig or more. Thepreferred pressure is from atmospheric (0 psig) up to about 1000 psig.As a general rule, a pressure of 20 to 800 psig is most preferred.

The selection of an inert organic solvent medium to be employed in thesolution or slurry process embodiments of this invention is not toocritical, but the solvent should be inert to the supportedorganometallic catalyst and olefin polymer produced, and be stable atthe reaction temperature used. It is not necessary, however, that theinert organic solvent medium also serve as a solvent for the polymer tobe produced. Among the inert organic solvents applicable for suchpurposes may be mentioned saturated aliphatic hydrocarbons having fromabout 3 to 12 carbon atoms per molecule such as hexane, heptane,pentane, isooctane, purified kerosene and the like, saturatedcycloaliphatic hydrocarbons having from about 5 to 12 carbon atoms permolecule such as cyclohexane, cyclopentane, dimethylcyclopentane andmethylcyclohexane and the like and aromatic hydrocarbons having fromabout 6 to 12 carbon atoms per molecule such as benzene, toluene,xylene, and the like. Particularly preferred solvent media arecyclohexane, pentane, hexane and heptane.

Hydrogen can be introduced into the polymerization reaction zone inorder to decrease the molecular weight of the polymers produced (i.e.,give a much higher Melt Index, MI). Partial pressure of hydrogen whenhydrogen is used can be within the range of 5 to 100 psig, preferably 25to 75 psig. The melt indices of the polymers produced in accordance withthe instant invention can range from about 0.1 to about 70 or evenhigher.

More detailed description of suitable polymerization conditionsincluding examples of particle form, solution and fluidized bedpolymerization arrangements are found in Karapinka; U.S. Pat. No.3,709,853; Issued Jan. 9, 1973 and Karol et al; U.S. Pat. No. 4,086,408;Issued Apr. 25, 1978. Both of these patents are incorporated herein byreference.

Hydrogenation

SSZ-75 can be used in a catalyst to catalyze hydrogenation of ahydrocarbon feed containing unsaturated hydrocarbons. The unsaturatedhydrocarbons can comprise olefins, dienes, polyenes, aromatic compoundsand the like.

Hydrogenation is accomplished by contacting the hydrocarbon feedcontaining unsaturated hydrocarbons with hydrogen in the presence of acatalyst comprising SSZ-75. The catalyst can also contain one or moremetals of Group VIB and Group VIII, including salts, complexes andsolutions thereof. Reference to these catalytically active metals isintended to encompass such metals or metals in the elemental state or insome form such as an oxide, sulfide, halide, carboxylate and the like.Examples of such metals include metals, salts or complexes wherein themetal is selected from the group consisting of platinum, palladium,rhodium, iridium or combinations thereof, or the group consisting ofnickel, molybdenum, cobalt, tungsten, titanium, chromium, vanadium,rhenium, manganese and combinations thereof.

The hydrogenation component of the catalyst (i.e., the aforementionedmetal) is present in an amount effective to provide the hydrogenationfunction of the catalyst, preferably in the range of from 0.05 to 25% byweight.

Hydrogenation conditions, such as temperature, pressure, spacevelocities, contact time and the like are well known in the art.

EXAMPLES

The following examples demonstrate but do not limit the presentinvention.

Example 1 Synthesis of Al-Containing SSZ-75

1.5 mM of tetramethylene-1,4-bis-(N-methylpyrrolidinium) dication SDA (3mM OH⁻) was mixed in a Teflon cup (for a Parr 23 ml reactor) with 1.26grams of tetraethylorthosilicate and the cup was placed in a hood toevaporate (as ethanol is formed from hydrolysis) over several days. Whenall of the visible liquid was gone, the Teflon cup was reweighed andwater was added to bring the H₂O/SiO₂ mole ratio to about four. Then, 12mg of Reheiss F2000 (50% Al₂O₃) was added and dissolved into thereaction mixture. This represents a starting synthesis mole ratio ofSiO₂/Al₂O₃ of 100. Lastly, 0.135 gram of 50% HF was added using aplastic pipette. The gel was mixed with a plastic spatula and then theresulting reaction mixture was heated in a closed vessel rotating at 43RPM at 150° C. for 16 days. A crystalline product formed which wasrecovered and found by X-ray diffraction analysis to be molecular sieveSSZ-75.

Example 2 Synthesis of Al-Containing SSZ-75

The procedure described in Example 1 was repeated, except that thesource of aluminum was LZ-210 zeolite (a form of dealuminated FAU) andthe SiO₂/Al₂O₃ mole ratio was 70. The reaction formed SSZ-75 in 10 days.

Example 3 Synthesis of Al-Containing SSZ-75

The procedure described in Example 1 was repeated, except that thesource of aluminum was Catapal B (a form of pseudoboehmite alumina). Thereaction formed SSZ-75 in 10 days.

Examples 4-7 Synthesis of All-Silica SSZ-75

A procedure similar to that of Example 1 was repeated using the reactionmixture (expressed as mole ratios) and conditions shown in the tablebelow. The reactions were run until a crystalline product was observedby SEM, and then the product was recovered. The products are also shownin the table.

SDA/ Ex. SiO₂ NH₄F/SiO₂ HF/SiO₂ H₂O/SiO₂ ° C./RPM Prod. 4 0.50 0.0 0.505.0 150/43 SSZ-75 5 0.40 0.1 0.40 5.0 150/43 SSZ-75 6 0.30 0.2 0.30 5.0150/43 MTW 7 0.20 0.3 0.20 5.0 150/43 Amor. ZSM-48

Example 8 Calcination of SSZ-75

The product from Example 1 was calcined in the following manner. A thinbed of material was heated in a flowing bed of air in a muffle furnacefrom room temperature to 120° C. at a rate of 1° C. per minute and heldat 120° C. for two hours. The temperature is then ramped up to 540° C.at the same rate and held at this temperature for three hours, afterwhich it was increased to 594° C. and held there for another threehours.

Example 9 Conversion of Methanol

The calcined material of Example 8 (0.10) gram) was pelleted and meshed(with recycling) to 20-40 mesh and packed into a ⅜ inch stainless steelreactor. After sufficient purge with nitrogen carrier gas (20 cc/min),the catalyst was heated to 750° F. (399° C.). A feed of 22.5% methanolin water was introduced into the reactor via syringe pump at a rate of1.59 cc/hr. A sample of the effluent stream was diverted to an on-linegas chromatograph at ten minute point of feed introduction. SSZ-75showed the following behavior:

Methanol conversion=100%No dimethylether detectedC₂-C₄ is about 70% of the productC₅₊ showed a mixture of olefins and saturatesAromatics were made with ethylbenzene the most abundant single productTrimethylbenzene isomers were observed as the heaviest products

At 100 minutes on stream the SSZ-75 was fouling, but still produced thesame products (although very few aromatics were observed).

1. A process for converting oxygenated hydrocarbons comprisingcontacting said oxygenated hydrocarbon under conditions to produceliquid products with a catalyst comprising a molecular sieve having amole ratio of at least 15 of an oxide of a first tetravalent element toan oxide of a second tetravalent element which is different from saidfirst tetravalent element, trivalent element, pentavalent element ormixture thereof and having, after calcination, the X-ray diffractionlines of Table II.
 2. The process of claim 1 wherein the oxygenatedhydrocarbon is a lower alcohol.
 3. The process of claim 2 wherein thelower alcohol is methanol.